As the variety of devices that have the capability of data presentation content (such as video) playback has increased, and as maximum bandwidth capacity for networks delivering the data presentation content has increased, so has user expectations for quality and speed of the playback of the delivered data presentation content. A prevalent standard used to support video downloads to different types of client devices over different network conditions is Hypertext Transfer Protocol (HTTP) Live Streaming (HLS). HLS, as described in Internet Engineering Task Force (IETF) Internet Draft HTTP Live Streaming publication (Pantos & May; ver. 10; Oct. 15, 2012-Apr. 18, 2013, and all subsequent versions (collectively referred herein to as HLS, the HLS draft specification, or the HLS standard)), is a client-driven protocol that divides a video presentation into discreet chunks, which can be downloaded separately and played in sequential order. While this approach makes effective use of network resources on average, degradation in user experience can result when the client device switches between variant streams having different bit rates, while playing the video presentation.
For example, the network providing the video presentation may include a server that reconfigures its encoder for different bit rates in order to provide the variant streams having the different bit rates. Each reconfiguration takes time, sometimes up to five or more seconds. In addition, normally, the changed bit rate stream has different encoding parameters, such as resolution, aspect ratio, profile/level, standard definition (SD)/high definition (HD), etc., than the previous data stream. This causes the client device to reset its video decoder to reconfigure to the new encoding parameters, which generates an additional playback delay. These delays produced by reconfiguration at the server side and at the client device side, as well as any decrease in resolution in the new data stream, can lead to significant video artifacts at the client device during video presentation playback.
Accordingly, there is a need for a novel method and apparatus for adaptive bit rate content delivery.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.